Semiconductor light-emitting device and method for fabricating the same

ABSTRACT

A semiconductor light-emitting device is provided. The semiconductor light-emitting device may include a light-emitting structure, an electrode, an ohmic layer, an electrode layer, an adhesion layer, and a channel layer. The light-emitting structure may include a compound semiconductor layer. The electrode may be disposed on the light-emitting structure. The ohmic layer may be disposed under the light-emitting structure. The electrode layer may include a reflective metal under the ohmic layer. The adhesion layer may be disposed under the electrode layer. The channel layer may be disposed along a bottom edge of the light-emitting structure.

The present application claims the benefit under 35 U.S.C. §119 ofKorean Patent Application No. 10-2009-0098361, filed in Korea on Oct.15, 2009, which is hereby incorporated by reference in its entirety.

BACKGROUND

1. Field

A semiconductor light-emitting device and a method for fabricating thesame are disclosed herein.

2. Background

Semiconductor light-emitting devices and methods for fabricating thesame are known. However, they suffer from various disadvantages.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments will be described in detail with reference to the followingdrawings in which like reference numerals refer to like elements, andwherein:

FIG. 1 is a sectional view of a semiconductor light-emitting deviceaccording to an embodiment;

FIG. 1A is a sectional view of a semiconductor light-emitting deviceaccording to another embodiment;

FIG. 2 is a sectional view of the semiconductor light-emitting device ofFIG. 1 taken along a line II-II;

FIGS. 3 to 13 are sectional views illustrating a process for fabricatinga semiconductor light-emitting device according to an embodiment;

FIG. 14 is a sectional view of a semiconductor light-emitting deviceaccording to another embodiment;

FIG. 15 is a sectional view of a semiconductor light-emitting deviceaccording to another embodiment;

FIG. 16 is a sectional view of a semiconductor light-emitting deviceaccording to another embodiment;

FIG. 17 is a sectional view of the semiconductor light-emitting deviceof FIG. 16 taken along line XVII-XVII; and

FIG. 18 is a sectional view of a light-emitting device package accordingto an embodiment.

DETAILED DESCRIPTION

Reference will now be made in detail to embodiments, examples of whichare illustrated in the accompanying drawings. Where possible, likereference numerals have been used to indicate like elements.

In the descriptions of embodiments, it should be understood that when alayer (or film), a region, a pattern, or a structure is referred to asbeing “on/under” a substrate, a layer (or film), a region, a pad, orpatterns, it may be directly on the substrate, the layer (or film), theregion, the pad, or the patterns, or intervening layers may also bepresent. Further, the reference about ‘on’ and ‘under’ each layer willbe made on the basis of the drawings. In the drawings, dimensions ofeach of the elements may be exaggerated for clarity of illustration, andthe dimensions of each of the elements may be different from the actualdimension of each of the elements.

Due to their physical and chemical characteristics, Group III-V nitridesemiconductors are being used as core materials for light-emittingdevices, such as light-emitting diodes (LEDs) and laser diodes (LDs). Anexample of the Group III-V nitride semiconductors is a nitridesemiconductor with a composition equation of In_(x)Al_(y)Ga_(1-x-y)N(0≦x≦1, 0≦y≦1, 0≦x+y≦1).

An LED is a kind of semiconductor device that is used as a light sourceor uses the characteristics of compound semiconductors to convertselectricity into light to exchange signals. Nitride semiconductor basedLEDs or LDs are widely used in light-emitting devices, and are appliedas light sources for various products, such as keypad light-emittingunits of mobile phones, electric light panels, and illumination devices.

FIG. 1 is a sectional view of a semiconductor light-emitting deviceaccording to an embodiment. FIG. 2 is a sectional view of thesemiconductor light-emitting device of FIG. 1 taken along line II-II.

Referring to FIGS. 1 and 2, a semiconductor light-emitting device 100may include a light-emitting structure 135, a channel layer 140, anohmic layer 150, an electrode layer 160, an adhesion layer 170, and aconductive support member 175.

The semiconductor light-emitting device 100 may be formed using acompound semiconductor, for example, a Group III-V compoundsemiconductor. The semiconductor light-emitting device 100 may emitlight of a visible-ray region, such as blue, green, and red light, andmay emit light of an ultraviolet region. The semiconductorlight-emitting device 100 may vary in shape and structure within thetechnical scope of embodiments.

The light-emitting structure 135 may include a first conductivity typesemiconductor layer 110, an active layer 120, and a second conductivitytype semiconductor layer 130. The first conductivity type semiconductorlayer 110 may be formed using, for example, a Group III-V compoundsemiconductor doped with a first conductivity type dopant. For example,the Group III-V compound semiconductor may include at least one selectedfrom the group consisting of GaN, AlN, AlGaN, InGaN, InN, InAlGaN,AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. For example, if the firstconductivity type semiconductor layer 110 is formed of an N typesemiconductor, the first conductivity type dopant may be selected fromthe Group V elements. The first conductivity type semiconductor layer110 may be formed to have a single-layer or multi-layer structure;however, embodiments are not limited thereto.

An electrode 115 may be disposed on the first conductivity typesemiconductor layer 110. The electrode 115 may branch in a patternshape; however, embodiments are not limited thereto. A top surface ofthe first conductivity type semiconductor layer 110 may be formed tohave a roughness pattern 112 to improve light extraction efficiency.Further, a top surface of the electrode 115 may be formed to have aroughness pattern as well; however, embodiments are not limited thereto.

The active layer 120 may be disposed under the first conductivity typesemiconductor layer 110. The active layer 120 may be formed to have, forexample, a single or multi quantum well structure. The active layer 120may be formed of, for example, a Group III-V compound semiconductor tohave a period of a well layer and a barrier layer. For example, theactive layer 120 may be formed to have an InGaN well layer/a GaN barrierlayer or an InGaN well layer/an ALGaN barrier layer.

A conductive clad layer (not shown) may be formed on and/or under theactive layer 120. For example, the conductive clad layer may be formedof an AlGaN-based semiconductor.

The second conductivity type semiconductor layer 130 may be disposedunder the active layer 120. The second conductivity type semiconductorlayer 130 may be formed using, for example, a Group III-V compoundsemiconductor doped with a second conductivity type dopant. For example,the Group III-V compound semiconductor may include at least one selectedfrom the group consisting of GaN, AlN, AlGaN, InGaN, InN, InAlGaN,AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. For example, if the secondconductivity type semiconductor layer 110 is formed of a P typesemiconductor, the second conductivity type dopant may be selected fromthe Group III elements. The second conductivity type semiconductor layer130 may be formed to have, for example, a single-layer or multi-layerstructure; however, embodiments are not limited thereto.

The light-emitting structure 135 may further include a thirdconductivity type semiconductor layer 134, which may be of the firstconductivity type, disposed under the second conductivity typesemiconductor layer 130, as shown in FIG. 1A. The third conductivitytype semiconductor layer may be opposite in polarity to the secondconductivity type semiconductor layer 130. Also, the first conductivitytype semiconductor layer 110 may be a P-type semiconductor layer, andthe second conductivity type semiconductor layer 130 may be an N-typesemiconductor layer. Accordingly, the light-emitting structure 135 mayinclude at least one of an N-P junction structure, a P-N junctionstructure, an N-P-N junction structure, or a P-N-P junction structure.

The channel layer 140 and the ohmic layer 150 may be disposed under thesecond conductivity type semiconductor layer 130 or the thirdconductivity type semiconductor layer 134. Hereinafter, for conveniencein description, it is assumed that the second conductivity typesemiconductor layer 130 is disposed as a lowermost layer of thelight-emitting structure 135.

The channel layer 140 may be formed along outer edges of the secondconductivity type semiconductor layer 130 and the adhesion layer 170.Herein, an edge region 105 of the light-emitting structure 135 is achannel region where the channel layer 140 and/or an insulating layer180 may be exposed.

An inner region D0 of the channel layer 140 may contact a bottom edge ofthe second conductivity type semiconductor layer 130, and an outerportion of the channel layer 140 may extend to an outside wall or edgeof the light-emitting structure 135. The channel layer 140 may beformed, for example, in a loop, ring, or frame shape along a bottom edgeof the second conductivity type semiconductor layer 130. The channellayer 140 may be formed in a closed-loop shape.

The channel layer 140 may be formed, for example, of at least one ofoxide, nitride, or an insulating material. For example, the channellayer 140 may be formed of at least one selected from the groupconsisting of ITO (indium tin oxide), IZO (indium zinc oxide), IZTO(indium zinc tin oxide), IAZO (indium aluminum zinc oxide), IGZO (indiumgallium zinc oxide), IGTO (indium gallium tin oxide), AZO (aluminum zincoxide), ATO (antimony tin oxide), GZO (gallium zinc oxide), SiO₂,SiO_(x), SiO_(x)N_(y), Si₃N₄, Al₂O₃, and TiO₂.

The channel layer 140 may prevent the occurrence of an electrical shorteven when the outer wall of the light-emitting structure 135 is exposedto moisture, thus making the semiconductor light-emitting device robustagainst high humidity. When the channel layer 140 is formed of atransparent material, irradiated laser beams may be transmitted in alaser scribing process, thereby preventing a metal material from beingfragmented due to laser irradiation. Accordingly, an interlayer short insidewalls of the light-emitting structure 135 may be prevented.

The channel layer 140 may provide a predetermined interval between theadhesion layer 170 and an outer wall of each layer 110/120/130 of thelight-emitting structure 135.

The ohmic layer 150 may be disposed inside the channel layer 130 andunder the second conductivity type semiconductor layer 130. The ohmiclayer 150 may ohmic-contact the second conductivity type semiconductorlayer 130. For example, the ohmic layer 150 may be embodied in ITO, IZO,IZTO, IAZO, IGZO, IGTO, AZO, or ATO. That is, the ohmic layer 150 mayselectively use a conductive oxide and a metal. For example, the ohmiclayer 150 may be formed in, for example, a single-layer or multi-layerstructure using at least one of ITO (indium tin oxide), IZO (indium zincoxide), IZTO (indium zinc tin oxide), IAZO (indium aluminum zinc oxide),IGZO (indium gallium zinc oxide), IGTO (indium gallium tin oxide), AZO(aluminum zinc oxide), ATO (antimony tin oxide), GZO (gallium zincoxide), IrOx, RuOx, RuOx/ITO, Ni, Ag, Ni/IrOx/Au, or Ni/IrOx/Au/ITO.

An end portion 152 of the ohmic layer 150 may contact an inner bottom ofthe channel layer 140. The end portion 152 of the ohmic layer 150 maynot be exposed outside of the chip by being spaced apart from the outerwall of the adhesion layer 170 by a predetermined distance D1.Accordingly, exfoliation in the interface between the ohmic layer 150and other layers may be prevented. Also, the end portion 152 of theohmic layer 150 may be formed as a cover type under an inner end of thechannel layer 140, thereby protecting the inner end (inner surface) ofthe channel layer 140.

Also, a current blocking layer 145 may be disposed under the secondconductivity type semiconductor layer 130. The current blocking layer145 may be formed in the ohmic layer 150, between the ohmic layer 150and the second conductivity type semiconductor layer 130, or between theelectrode layer 160 and the ohmic layer 150.

The current blocking layer 145 may be formed to have a lower electricalconductivity than the electrode layer 160 or the adhesion layer 170. Forexample, the current blocking layer 145 may be formed of at least one ofITO, IZO, IZTO, IAZO, IGZO, IGTO, AZO, ATO, ZnO, SiO₂, SiO_(x),SiO_(x)N_(y), Si₃N₄, Al₂O₃, or TiO₂. If the electrode layer 160 isformed of Ag, the current blocking layer 145 may be formed, for example,of ITO, ZnO, or SiO₂.

The current blocking layer 145 may be formed to correspond to a shape ofthe electrode 115. Also, the current blocking layer 145 may be formed ina region corresponding to the electrode 115. A size of the currentblocking layer 145 may vary according to current distribution.

The electrode layer 160 may be disposed under the ohmic layer 150 toserve as a reflection layer. The electrode layer 160 may be formed ofone selected from the group consisting of Ag, Ni, Al, Rh, Pd, Ir, Ru,Mg, Zn, Pt, Au, Hf, and a combination thereof. Also, the electrode layer160 may be formed in a multi-layer structure using a metal material anda conductive oxide material, such as IZO, IZTO, IAZO, IGZO, IGTO, AZO,and ATO. For example, the electrode layer 160 may be formed, forexample, of IZO/Ni, AZO/Ag, IZO/Ag/Ni, or AZO/Ag/Ni.

The electrode layer 160 may be formed under the ohmic layer 160, suchthat its end portion 162 does not contact the ohmic layer 150.Accordingly, the problem of a decrease in adhesive force due to contactbetween the oxide material (for example, ITO and SiO2) of the channellayer 140 and the metal (for example, Ag) of the electrode layer 160 maybe reduced and chip reliability improved. The electrode layer 160 mayreflect light incident from the light-emitting structure 135, thusincreasing light extraction efficiency.

The adhesion layer 170 may be disposed under the electrode layer 160.The adhesion layer 170 may include a barrier metal or a bonding metal.For example, the adhesion layer 170 may include at least one of Ti, Au,Sn, Ni, Cr, Ga, In, Bi, Cu, Ag, or Ta.

The adhesion layer 170 may be disposed under the electrode layer 160 andthe channel layer 140. The adhesion layer 170 may be exposed at an outerwall of the chip. The adhesion layer 170 may contact the electrode layer160, the end portion 152 of the ohmic layer 150, and the channel layer140 to increase adhesive force between the layers.

The conductive support member 175 may be disposed under the adhesionlayer 170. The conductive support member 175 may be a base substrateformed using, for example, copper (Cu), aurum (Au), nickel (Ni),molybdenum (Mo), copper-tungsten (Cu—W), or a carrier wafer (forexample, Si, Ge, GaAs, ZnO, SiC, GaN, and SiGe). The conductive supportmember 175 may also be formed, for example, using a conductive sheet.

An edge of the light-emitting structure 135 may be inclined. Theinsulating layer 180 may be formed along the edge of the light-emittingstructure 135. The insulating layer 180 may have a bottom portion 182disposed on the channel layer 140 and a top portion 184 disposed aroundthe first conductivity type semiconductor layer 110. Accordingly,adhesive force to the insulating layer 180 may be increased andinterlayer short of the light-emitting structure 135 may be prevented.

Referring to FIG. 2, an inner portion of the channel layer 140 may bedisposed in a semiconductor region E1. Also, an outer portion of thechannel layer 140 may be disposed in regions C1 and C2 outside of thesemiconductor region E1. The current blocking layer 145 may be disposedin an inner region of the ohmic layer 150, for example, in a regioncorresponding to the electrode 115 of FIG. 1.

FIGS. 3 to 13 are sectional views illustrating a process for fabricatinga semiconductor light-emitting device according to an embodiment.Referring to FIGS. 3 and 4, a substrate 101 may be loaded on growthequipment, and a Group II to VI compound semiconductor may be formedthereon in a layer or pattern shape. The growth equipment may be, forexample, one of a PVD (physical vapor deposition) equipment, a CVD(chemical vapor deposition) equipment, a PLD (plasma laser deposition)equipment, a dual-type thermal evaporator, a sputtering equipment, or anMOCVD (metal organic chemical vapor deposition) equipment; however,embodiments are not limited thereto.

The substrate 101 may be formed, for example, of at least one selectedfrom the group consisting sapphire (Al₂0₃), GaN, SiC, ZnO, Si, GaP, InP,Ga₂0₃, conductive material, and GaAs. A roughness pattern may be formedin a top surface of the substrate 101. Also, a layer or pattern based ona Group II to VI compound semiconductor, for example, at least one of anZnO layer (not illustrated), a buffer layer (not illustrated) and anundoped semiconductor layer (not illustrated) may be formed on thesubstrate 101. The buffer layer or the undoped semiconductor layer maybe formed using a group III-V compound semiconductor. The buffer layermay reduce a lattice constant with the substrate 101, and the undopedsemiconductor layer may be formed, for example, of an undoped GaN-basedsemiconductor.

A first conductivity type semiconductor layer 110 may be formed on thesubstrate 101. An active layer 120 may be formed on the firstconductivity type semiconductor layer 110. A second conductivity typesemiconductor layer 130 may be formed on the active layer 120.

The first conductivity type semiconductor layer 110 may be formed using,for example, a Group III-V compound semiconductor doped with a firstconductivity type dopant. For example, the Group III-V compoundsemiconductor may include at least one selected from the groupconsisting of GaN, AlN, AlGaN, InGaN, InN, InAlGaN, AlInN, AlGaAs, GaP,GaAs, GaAsP, and AlGaInP. For example, if the first conductivity typesemiconductor layer 110 is formed of a N type semiconductor, the firstconductivity type dopant may be selected from the Group V elements. Thefirst conductivity type semiconductor layer 110 may be formed to have,for example, a single-layer or multi-layer structure; however,embodiments are not limited thereto.

The active layer 120 may be formed on the first conductivity typesemiconductor layer 110. The active layer 120 may be formed to have, forexample, a single or multi quantum well structure. The active layer 120may be formed, for example, of a Group III-V compound semiconductor tohave a period of a well layer and a barrier layer, for example, a periodof an InGaN well layer/a GaN barrier layer or an InGaN well layer/anAlGaN barrier layer.

A conductive clad layer may be formed on and/or under the active layer120. For example, the conductive clad layer may be formed of anAlGaN-based semiconductor.

The second conductivity type semiconductor layer 130 may be formed onthe active layer 120. The second conductivity type semiconductor layer130 may be formed using, for example, a Group III-V compoundsemiconductor doped with a second conductivity type dopant. For example,the Group III-V compound semiconductor may include at least one selectedfrom the group consisting of GaN, AlN, AlGaN, InGaN, InN, InAlGaN,AlInN, AlGaAs, GaP, GaAs, GaAsP, and AlGaInP. For example, if the secondconductivity type semiconductor layer 110 is formed of a P typesemiconductor, the second conductivity type dopant may be selected fromthe Group III elements. The second conductivity type semiconductor layer130 may be formed to have, for example, a single-layer or multi-layerstructure; however, embodiments are not limited thereto.

The first conductivity type semiconductor layer 110, the active layer120, and the second conductivity type semiconductor layer 130 mayconstitute a light-emitting structure 135. Also, a third conductivitytype semiconductor layer 134, for example, a N-type semiconductor layeror a P-type semiconductor layer may be formed on the second conductivitytype semiconductor layer 130. Accordingly, the light-emitting structure135 may be formed to include at least one of a N-P junction structure, aP-N junction structure, a N-P-N junction structure, and a P-N-P junctionstructure.

A channel layer 140 may be formed in each chip boundary region (channelregion). The channel layer 140 may be formed around each chip region byusing, for example, a mask pattern. The channel layer 140 may be formed,for example, in a loop, ring or frame shape. The channel layer 140 maybe formed, for example, of at least one of oxide, nitride, or aninsulating material. For example, the channel layer 140 may be formed ofat least one selected from the group consisting of ITO (indium tinoxide), IZO (indium zinc oxide), IZTO (indium zinc tin oxide), IAZO(indium aluminum zinc oxide), IGZO (indium gallium zinc oxide), IGTO(indium gallium tin oxide), AZO (aluminum zinc oxide), ATO (antimony tinoxide), GZO (gallium zinc oxide), SiO₂, SiO_(x), SiO_(x)N_(y), Si₃N₄,Al₂O₃, and TiO₂. For example, the channel layer 140 may be formed, forexample, by a sputtering process or a deposition process.

Referring to FIGS. 4 and 5, a current blocking layer 145 may be formedon the second conductivity type semiconductor layer 130. The currentblocking layer 145 may be formed using, for example, a mask pattern. Thecurrent blocking layer 145 may be formed of the same material as or adifferent material from the channel layer 140. The formation order mayvary according to such a material difference.

The current blocking layer 145 may be formed to have a lower electricalconductivity than the second conductivity type semiconductor layer 130.For example, the current blocking layer 145 may be formed of at leastone of ITO, IZO, IZTO, IAZO, IGZO, IGTO, AZO, ATO, ZnO, SiO₂, SiO_(x),SiO_(x)N_(y), Si₃N₄, Al₂O₃, or TiO₂. The current blocking layer 145 maybe formed using, for example, a mask pattern. Further, the currentblocking layer 145 may be formed to correspond to a region for anelectrode. The current blocking layer 145 may be formed in a same shapeas an electrode pattern; however, embodiments are not limited thereto.

Referring to FIGS. 5 and 6, an ohmic layer 150 may be formed on thesecond conductivity type semiconductor layer 130 to ohmic-contact thesecond conductivity type semiconductor layer 130. The ohmic layer 150may be formed on the second conductivity type semiconductor layer 130and the current blocking layer 145 to reduce contact resistance. Incomparison with adjacent regions, the current blocking layer 145 mayhave little current flowing therethrough, thus supplying a current in adiffused manner.

An end portion 152 of the ohmic layer 150 may be formed to overlap withthe channel layer 140. In one chip region, the end portion 152 of theohmic layer 150 may overlap an inner end of the channel layer 140 by apredetermined width D2, thereby protecting the inner end of the channellayer 140. The end portion 152 of the ohmic layer 150 may not be exposedoutside of the chip by being spaced apart from the chip boundary or wallby a predetermined distance D1.

Referring to FIGS. 6 and 7, an electrode layer 160 may be formed on theohmic layer 150. The electrode layer 160 may have a reflection functionand may reflect incident light, thus improving light extractionefficiency. The electrode layer 160 may be formed, for example, of oneselected from the group consisting of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg,Zn, Pt, Au, Hf, and a combination thereof. Also, the electrode layer 160may be formed, for example, in a multi-layer structure using a metalmaterial and a conductive oxide material, such as IZO, IZTO, IAZO, IGZO,IGTO, AZO, and ATO. For example, the electrode layer 160 may be formedof IZO/Ni, AZO/Ag, IZO/Ag/Ni, or AZO/Ag/Ni.

The electrode layer 160 may be formed on the ohmic layer 150, such thatits end portion 162 does not contact the channel layer 140. Accordingly,the problem of a decrease in the adhesive force due to contact betweenthe oxide material (for example, ITO and SiO₂) of the channel layer 140and the metal (for example, Ag) of the electrode layer may be reduced,and chip reliability improved.

Referring to FIGS. 7 and 8, an adhesion layer 170 may be formed on theelectrode layer 160. The adhesion layer 170 may include, for example, abarrier metal or a bonding metal. For example, the adhesion layer 170may include at least one of Ti, Au, Sn, Ni, Cr, Ga, In, Bi, Cu, Ag, orTa.

The adhesion layer 170 may be formed on the electrode layer 160 and thechannel layer 140. The adhesion layer 170 may be formed in a chipboundary region. The adhesion layer 170 may contact the electrode layer160, the end portion 152 of the ohmic layer 150, and the channel layer140 to increase interlayer adhesive force.

A conductive support member 175 may be formed on the adhesion layer 170.The conductive support member 175 may be a base substrate formed using,for example, copper (Cu), aurum (Au), nickel (Ni), molybdenum (Mo),copper-tungsten (Cu—W), or a carrier wafer (for example, Si, Ge, GaAs,ZnO, SiC, GaN, and SiGe). The conductive support member 175 may be, forexample, bonded to the adhesion layer 170, may be formed of a platinglayer, or may be attached in the shape of a conductive sheet.

Referring to FIGS. 8 to 10, the conductive support member 175 become thebase, and the substrate 101 removed. For example, the substrate 101 maybe removed by, for example, a Laser Lift Off (LLO) process. The LLOprocess may irradiate a laser beam of a predetermined wavelength ontothe substrate 101 to remove the substrate 101. If another semiconductorlayer (for example, a buffer layer) or an air gap is present between thesubstrate 101 and the first conductivity type semiconductor layer 110,the substrate 101 may be removed using, for example, a wet etchant.

If the channel layer 140 is formed of transparent material, when thelaser irradiates a laser beam to the interface between the substrate 101and the semiconductor layer or the interface between the twosemiconductor layers, the irradiated laser beam may penetrate thechannel layer 140, thereby preventing metal fragments from beinggenerated in the channel region due to laser irradiation and preventingan outer wall of each layer of the light-emitting structure 135.

A polishing process based on ICP/RIE (Inductively coupledPlasma/Reactive Ion Etching) may be performed on the surface of thefirst conductivity type semiconductor layer 110 removed of the substrate101. Referring to FIGS. 10 and 11, the light-emitting structure 135 ofan inter-chip boundary region (for example, a channel region) may beremoved through, for example, an isolation etching process. A region 105removed through the isolation etching process may be etched to exposethe channel layer 140 in the chip boundary region; however, embodimentsare not limited thereto. A side surface A1 of the light-emittingstructure 135 may be inclined.

Thereafter, an etching process may be performed on a top surface of thefirst conductivity type semiconductor layer 110 to form a roughnesspattern 112. The roughness pattern 112 may improve light extractionefficiency.

Referring to FIGS. 11 to 13, an insulating layer 180 may be formedaround the light-emitting structure 135. The insulating layer 180 may beformed around the chip. That is, a bottom portion 182 may be formed onthe channel layer 140 and a top portion 184 formed around the topsurface of the first conductivity type semiconductor layer 110. Theinsulating layer 180 may be formed around the light-emitting structure135, thus preventing a short between the layers 110, 120 and 130. Also,the insulating layer 180 and the channel layer 140 may prevent moisturefrom infiltrating into the chip.

An electrode 115 may be formed on the first conductivity typesemiconductor layer 110. The electrode 115 may be formed in apredetermined pattern. The forming of the insulating layer 180 and theelectrode 115 may be performed before or after chip separation; however,embodiments are not limited thereto. A roughness pattern may be formedin a top surface of the electrode 115; however, embodiments are notlimited thereto.

Thereafter, the resulting structure may be separated into separate chipunits by a chip boundary. The chip separation may be performed using,for example, a laser or a breaking process.

FIG. 14 is a sectional view of a semiconductor light-emitting deviceaccording to another embodiment. Referring to FIG. 14, a semiconductorlight-emitting device 100A may include an electrode layer 160A disposedbetween a channel layer 140 and an adhesion layer 170. The electrodelayer 160A may be formed to have a larger length and/or width than thelight-emitting structure 135, thereby improving light reflectionefficiency.

Also, the electrode layer 160A may be formed under the ohmic layer 150and the channel layer 140 and may be exposed outside of the chip. Theohmic layer 150 may be formed to have a smaller length and/or width thanthe semiconductor layer, and the electrode layer 160A may be formed tohave a larger length and/or width than the semiconductor layer. Unlikethe previous embodiment, this embodiment may extend the electrode layer160A outside or to an outside edge of the chip, thus improving lightreflection efficiency.

FIG. 15 is a sectional view of a semiconductor light-emitting deviceaccording to another embodiment. Referring to FIG. 15, a semiconductorlight-emitting device 100B may include an ohmic layer 150A, a channellayer 140, an electrode layer 160A, an adhesion layer 170, and aconductive support member 175 that are disposed under the light-emittingstructure 135.

The ohmic layer 150A may ohmic-contact a bottom of a second conductivitytype semiconductor layer 130 and may extend outside or to an outer edgeof the chip. The ohmic layer 150A may extend from the secondconductivity type semiconductor layer 130 to a bottom of the channellayer 140.

The ohmic layer 150A may be formed under the electrode layer 160A.Accordingly, the ohmic layer 150A and the electrode layer 160A may beformed in a stack structure under the channel layer 140, and may beexposed outside the chip.

FIG. 16 is a sectional view of a semiconductor light-emitting deviceaccording to another embodiment. FIG. 17 is a sectional view of thesemiconductor light-emitting device of FIG. 16 taken along a lineXVII-XVII.

Referring to FIGS. 16 and 17, a semiconductor light-emitting device 100Cmay include a capping layer 155 disposed between a channel layer 140 andan electrode layer 160B. The capping layer 155 may be formed of amaterial having a good adhesive force with respect to the material ofthe channel layer 140, for example, a mixed metal of one or moreselected from the group consisting of Ti, Ni, Pt, Pd, Cu, Al, Ir, andRh. That is, the capping layer 155 may serve as an adhesion layer toimprove adhesive force between the metal and the oxide, thus reducingexfoliation outside the chip. The capping layer 155 may be formedbetween the channel layer 140 and the electrode layer 160B, thusincreasing adhesive force to the electrode layer 160B.

Also, an inner end of the capping layer 155 may contact a bottom surfaceof the second conductivity type semiconductor layer 130 through a spacebetween the channel layer 140 and the ohmic layer 150B. Accordingly, thesecond conductivity type semiconductor layer 130 may contact the ohmiclayer 150B, the channel layer 140, a current blocking layer 145 and thecapping layer 155. Therefore, the second conductivity type semiconductorlayer 130 may be protected by the channel layer 140 outside the chip,and a current may be provided through the ohmic layer 150B and thecapping layer 155 in the chip.

The capping layer 155 may have a higher electrical conductivity than theohmic layer 150B, thus diffusing current outside the chip. Further, thecapping layer 155 may be spaced apart from the ohmic layer 150B, or maybe formed to overlap a bottom of the ohmic layer 150B. This modificationmay be embodied within the technical scope of the inventive concept.Also, the electrode layer 160B and/or the adhesion layer 170 may contacta bottom surface of the capping layer 155.

Referring to FIG. 17, the capping layer 155 may be formed in, forexample, a loop, ring, or frame shape along a region between the ohmiclayer 150B and the channel layer 140. An inner end of the capping layer155 may be formed to have a roughness pattern. In this case, the ohmiclayer 150B may alternately contact the channel layer 140B and thecapping layer 155.

FIG. 18 is sectional view of a light-emitting device package accordingto an embodiment. Referring to FIG. 18, a light-emitting device packageaccording to this embodiment includes a body 20, a first lead electrode31, a second lead electrode 32, a semiconductor light-emitting device100, and a molding member 40. The first lead electrode 31 and the secondlead electrode 32 may be disposed at the body 20. The semiconductorlight-emitting device 100 may be electrically connected to the firstlead electrode 31 and the second lead electrode 32. The molding member40 may be configured to mold the semiconductor light-emitting device100. The body 20 may be formed to include, for example, siliconmaterial, synthetic resin, or metallic material, and an inclined surfacemay be formed around the semiconductor light-emitting device 100.

The first lead electrode 31 and the second lead electrode 32 may beelectrically disconnected from each other, and provide power to thesemiconductor light-emitting device 100. Also, the first lead electrode31 and the second lead electrode 32 may reflect light emitted from thesemiconductor light-emitting device 100, thus increasing lightefficiency. Also, the first lead electrode 31 and the second leadelectrode 32 may serve to discharge heat generated by the semiconductorlight-emitting device 100.

The semiconductor light-emitting device 100 may be disposed on the body20, or may be disposed on the first lead electrode 31 or the second leadelectrode 32. The semiconductor light-emitting device 100 may beelectrically connected by, for example, a wire to the first leadelectrode 31, and may be connected to the second lead electrode 32 in,for example, a die-bonding configuration.

The molding member 40 may mold the semiconductor light-emitting device100 to protect the semiconductor light-emitting device 100. Also, afluorescent material may be included in the molding member 40 to changea wavelength of light emitted from the semiconductor light-emittingdevice 100.

The semiconductor light-emitting device according to embodiments may bepackaged, for example, in a semiconductor substrate, a dielectricsubstrate, or a ceramic substrate (such as resin material or silicon),and may be used, for example, as a light source of a indication device,an illumination device, or a display device. Also, each embodiment isnot limited thereto and may be selectively applied to the otherembodiments.

As described above, embodiments disclosed herein may improve the lightextraction efficiency. Also, embodiments disclosed herein may improvereliability according to junctions between metal and nonmetal layers andbetween the metal layers under the semiconductor layer. Additionally,embodiments disclosed herein may improve chip reliability.

Embodiments disclosed herein may be applicable to any light-emittingdevice that provides light.

Embodiments disclosed herein provide a semiconductor light-emittingdevice capable of improving the adhesive force between layers disposedunder a light-emitting structure including a compound semiconductorlayer, and a method for fabricating the same.

According to an embodiment disclosed herein, a semiconductorlight-emitting device is provided that may include a light-emittingstructure including a compound semiconductor layer; an electrode on thelight-emitting structure; an ohmic layer under the light-emittingstructure; an electrode layer including a reflective metal under theohmic layer; an adhesion layer under the electrode layer; and a channellayer disposed along a bottom edge of the light-emitting structure.

According to another embodiment disclosed herein, a method forfabricating a semiconductor light-emitting device is provided that mayinclude forming a light-emitting structure including a compoundsemiconductor layer on a substrate; forming a transparent channel layeralong a top edge of the light-emitting structure; forming an ohmic layeron the light-emitting structure; forming an electrode layer including areflective metal on the ohmic layer; forming an adhesion layer on theelectrode layer; removing the substrate; etching the light-emittingstructure to expose the channel layer; and forming an electrode on thelight-emitting structure.

Any reference in this specification to “one embodiment,” “anembodiment,” “example embodiment,” etc., means that a particularfeature, structure, or characteristic described in connection with theembodiment is included in at least one embodiment of the invention. Theappearances of such phrases in various places in the specification arenot necessarily all referring to the same embodiment. Further, when aparticular feature, structure, or characteristic is described inconnection with any embodiment, it is submitted that it is within thepurview of one skilled in the art to effect such feature, structure, orcharacteristic in connection with other ones of the embodiments.

Although embodiments have been described with reference to a number ofillustrative embodiments thereof, it should be understood that numerousother modifications and embodiments can be devised by those skilled inthe art that will fall within the spirit and scope of the principles ofthis disclosure. More particularly, various variations and modificationsare possible in the component parts and/or arrangements of the subjectcombination arrangement within the scope of the disclosure, the drawingsand the appended claims. In addition to variations and modifications inthe component parts and/or arrangements, alternative uses will also beapparent to those skilled in the art.

What is claimed is:
 1. A semiconductor light-emitting device,comprising: an adhesion layer comprising a top surface and asubstantially planar bottom surface, the top surface having a firstportion that is substantially flat, and a second portion that has arecessed portion having bottom surfaces having different heights withreference to a bottom surface of the adhesion layer around the firstportion of the top surface of the adhesion layer; a reflective electrodedirectly on the adhesion layer, the reflective electrode comprising ametal material so as to serve as a reflective member; a light-emittingstructure directly on the reflective electrode comprising a firstconductivity type semiconductor layer, an active layer on the firstconductivity type semiconductor layer, and a second conductivity typesemiconductor layer on the active layer, a top surface of the secondconductivity type semiconductor layer having a roughness; a channellayer directly on the adhesion layer along a bottom edge of thelight-emitting structure, a top surface of the channel layer comprisinga first portion in directly contact with the first conductivity typesemiconductor layer, and a second portion; an insulating layer thatextends from the second portion of the channel layer to a top surface ofthe light-emitting structure; and an electrode on the light-emittingstructure, a top surface of the electrode having a roughness, whereinthe channel layer includes at least one of a group consisting of ITO,IZO, IZTO, IAZO, IGZO, IGTO, AZO, ATO, ZnO, SiO₂, SiO_(x), SiO_(x)N_(y),Si₃N₄, Al₂O₃, and TiO₂.
 2. The semiconductor light-emitting deviceaccording to claim 1, wherein the channel layer is formed of at leastone of a transparent oxide material, a transparent nitride material, ora transparent insulating material.
 3. The semiconductor light-emittingdevice according to claim 1, further comprising: at least one of anohmic layer or a current blocking layer between the first conductivitytype semiconductor layer and the reflective electrode.
 4. Thesemiconductor light-emitting device according to claim 3, wherein thechannel layer includes substantially the same material as the currentblocking layer.
 5. The semiconductor light-emitting device according toclaim 3, wherein the current blocking layer is formed of a materialhaving an electrical conductivity lower than that of the reflectiveelectrode.
 6. The semiconductor light-emitting device according to claim3, further comprising a conductive support member under the adhesionlayer, wherein the current blocking layer corresponds to a shape of theelectrode.
 7. The semiconductor light-emitting device according to claim3, wherein an inner portion of the channel layer contacts the ohmiclayer, and an outer portion of the channel layer contacts at least oneof the reflective electrode or the adhesion layer.
 8. The semiconductorlight-emitting device according to claim 1, further comprising a cappinglayer between the channel layer and the reflective electrode, thecapping layer comprising a mixed metal of one or more selected from agroup consisting of Ti, Ni, Pt, Pd, Cu, Al, Ir, and Rh.
 9. Thesemiconductor light-emitting device according to claim 8, wherein aninner end of the capping layer contacts at least one of the firstconductivity type semiconductor layer or the ohmic layer.
 10. Asemiconductor light-emitting device, comprising: a support member; anadhesion layer directly on the support member, the adhesion layercomprising a top surface and a substantially planar bottom surface, thetop surface having a first portion that is substantially flat, and asecond portion that has a recessed portion having different heights withreference to a bottom surface of the adhesion layer around the firstportion of the top surface of the adhesion layer; a reflective electrodedirectly on the adhesion layer, the reflective electrode comprising ametal material so as to serve as a reflective member; a light-emittingstructure comprising a first conductivity type semiconductor layer, anactive layer on the first conductivity type semiconductor layer, and asecond conductivity type semiconductor layer on the active layer; achannel layer disposed along outer edges of the first conductivity typesemiconductor layer, an end portion of the channel layer being indirectly contact with the first conductivity type semiconductor layer;and a current blocking layer between the reflective electrode and thefirst conductivity type semiconductor layer, wherein the channel layerincludes at least one of a group consisting of ITO, IZO, IZTO, IAZO,IGZO, IGTO, AZO, ATO, ZnO, SiO₂, SiO_(x), SiO_(x)N_(y), Si₃N₄, Al₂O₃,and TiO₂.
 11. The semiconductor light-emitting device according to claim10, further comprising an electrode on the second conductivity typesemiconductor layer.
 12. The semiconductor light-emitting deviceaccording to claim 10, wherein the reflective electrode comprises a padand branch-type metal pattern connected to the pad.
 13. Thesemiconductor light-emitting device according to claim 10, wherein anouter side of the light-emitting structure is inclined.
 14. Thesemiconductor light-emitting device according to claim 1, wherein thereflective electrode is disposed on the recessed portions of theadhesion layer.
 15. The semiconductor light-emitting device according toclaim 1, wherein the second portion has a bottom surface of the recessedportion at a center area of the second portion higher than that at anedge area of the second portion.
 16. The semiconductor light-emittingdevice according to claim 10, wherein the reflective electrode isdisposed on the recessed portions of the adhesion layer.
 17. Thesemiconductor light-emitting device according to claim 10, wherein thesecond portion has a bottom surface of the recessed portion at a centerarea of the second portion higher than that at an edge area of thesecond portion.